Metastatic Pulmonary Calcinosis in a Patient on Peritoneal Dialysis: A Case Report

Abstract

Chronic kidney disease–mineral and bone disorder (MBD) is a common complication in dialysis patients, contributing to soft tissue and vascular calcifications. Metastatic pulmonary calcification, though frequently found at autopsy, is rarely recognized clinically, particularly among patients on peritoneal dialysis (PD). We report the case of a 40-year-old Tunisian woman with end-stage renal disease of unknown etiology, treated with PD since 2015 using dextrose-based dialysis solutions with a calcium concentration of 2.5 mEq/L. Icodextrin was considered but not prescribed due to financial constraints and lack of insurance coverage. The patient had secondary hyperparathyroidism, persistent hyperphosphatemia, and hypocalcemia. Management relied on oral calcium carbonate, as noncalcium phosphate binders were unavailable. Following subtotal parathyroidectomy, histology confirmed nodular hyperplasia. A drop in parathyroid hormone levels to 9 ng/L was observed and hyperphosphatemia and hypocalcemia persisted despite ongoing calcium supplementation. In 2022, the patient presented with nonspecific respiratory symptoms. Chest computed tomography revealed diffuse pulmonary calcifications and flower-like bronchovascular deposits. Lung biopsy confirmed metastatic pulmonary calcinosis. Calcium supplementation was discontinued, and the patient was transitioned to hemodialysis. She was lost to follow-up 1 month later. This case underscores the importance of individualized management of MBD in patients undergoing PD, particularly in low-resource settings where access to essential treatments remains limited. It emphasizes the importance of context-specific monitoring and preventive strategies to avoid severe complications.